The present invention is directed to improved methods for anesthesia in mammals, especially humans. More particularly, improved procedures for local anesthesia are provided which overcome many of the shortcomings of prior methods. The present invention is directed to procedures for anesthesia, especially "local" anesthesia of the regions in and around the mouth. In the present context, "local" anesthesia includes all forms of soft tissue anesthesia including infiltrative and "blocking" anesthesia. As applied to anesthesia of the mouth and associated regions, the present invention is directed to all forms of such anesthesia, especially infiltrative soft tissue anesthesia, alveolar, mandibular, and other blocks and those other means of local anesthesia appropriate to oral surgery, dental restoration, and the like which are known to those of ordinary skill of the art.
As traditionally practiced, oral anesthesia comprises the application, such as by injection, of one or more anesthetic agents into appropriate regions of the mouth and surrounding tissues. In common practice, vasoconstrictors such as catchecolamines including epinephrine, norepinephrine and similar species together with other vasoconstrictors, may be added to anesthetics to prolong the duration of anesthesia in the highly vascular environment of the mouth. This prolongation of the anesthetic effect is beneficial from the standpoint of providing increased working time for the oral surgeon or dentist, but suffers from certain shortcomings. Thus, self-inflicted tongue, lip, and cheek ulcerations are commonly seen as a result of the prolonged loss of soft tissue sensation in the mouth. Such physical injury may be more harmful than the oral procedure itself. Corollarily, the persistence of anesthesia in oral tissues interferes with the normal activities of patients receiving oral anesthesia coupled with vasoconstriction co-treatment; patient dissatisfaction may result. The employment of vasoconstrictors with oral anesthetics leads to further difficulties from a practical standpoint. Thus, it is difficult to secure patient information requiring oral sensation when vasoconstrictors are co-administered with oral anesthetics. It is, accordingly, necessary to detain a patient for a significant period of time if such information, such as the feel or comfort of an oral restoration, is to be obtained. Patient "feedback" is therefore difficult to obtain. Moreover, it is inconvenient to work on more than one section of a mouth during one visit to an oral surgeon or dentist since simultaneous local anesthesia of pluralities of mouth regions is generally contraindicated.